Search Results (133)

Cotton is one of the most important crops worldwide, having considerable economic importance in Greece. This study aimed to evaluate the fiber quality traits of partially interspecific cotton lines under contrasting irrigation and nitrogen environments within a strip-split block field design. Experiments conducted over two consecutive years include a control (commercial cultivar Celia) and four partially interspecific lines of the Pa7 generation (Gossypium hirsutum × G. barbadense). Three irrigation and two nitrogen fertilization levels were applied. Significant differences were observed among genotypes and environments for all fiber quality traits, with some year-to-year variation. Genotypic response for yellowness was influenced by fertilization. Across the two experimental years, a strong Fertilization × Environment interaction was observed, and in the second year, a Genotype × Fertilization × Environment interaction was detected for the uniformity index. Pa7 lines consistently outperformed Celia in fiber length (≈33 vs. 30 mm) and elongation (≈7.0 vs. 5.5%), while exhibiting higher yellowness values. Fiber strength, micronaire, uniformity, and reflectance varied between years but remained within acceptable ranges. Overall, Pa7 lines demonstrated superior fiber quality and stability under variable conditions, highlighting their potential for breeding programs. These findings support the importance of integrating interspecific germplasm with suitable irrigation–nitrogen management to improve cotton fiber performance and resilience under diverse cultivation environments. Full article

Intercropping is an eco-friendly, sustainable agricultural model that significantly improves yield stability, nutrient use efficiency, and soil health through spatiotemporal niche complementarity, increases biodiversity, and improves soil health. Water and nitrogen play crucial roles in limiting and regulating efficient resource utilization and ecological sustainability in intercropping systems. Synchronizing water and nitrogen inputs to match crop demands optimizes the spatiotemporal distribution of these resources, alleviates interspecific competition, and promotes mutualistic interactions, which significantly impacts crop growth, yield, and soil environment. This paper reviews the mechanisms of intercropping and water–nitrogen coupling regulation, aligning water and nitrogen supply with crop growth patterns, spatial configuration parameters, irrigation management techniques, and environmental climate change, and explores the response mechanisms of water–nitrogen coupling on crop growth, yield, and soil environmental adaptation. It can provide some references for researchers, extension agents, and policymakers. Research indicates that water–nitrogen coupling can enhance photosynthetic efficiency, promote root development, optimize nutrient uptake, and improve soil water dynamics, nitrogen cycling, and microbial community structures. Intercropping enhances the climate resilience of agricultural systems by leveraging species complementarity for resource utilization, strengthening ecosystem stability, and improving buffering capacity against climate change impacts such as extreme precipitation and temperature fluctuations. Future studies should further elucidate the differential effect of water–nitrogen coupling across regions and climatic conditions, focusing on multidimensional integrated administration strategies. Combining precision agriculture technologies and climate change predictions facilitates the development of more adaptive water–nitrogen coupling models to provide theoretical support and technical guarantees for sustainable agriculture. Full article

Drought is a global issue that affects agricultural productivity and sustainable development. The application of Bacillus subtilis has significant potential in alleviating drought stress and increasing yield. However, it is not yet clear how Bacillus subtilis affects microbial populations, crop yield, and the biochemical characteristics of rhizosphere soil, as well as the interactions among these factors. In this study, cotton was used as the experimental crop, and different application rates of Bacillus subtilis (0 kg·ha⁻¹ and 45 kg·ha⁻¹ (B)) and drought stress levels (H represents conventional irrigation, 350 mm; L represents 80% of conventional irrigation, 280 mm) were set as three replicates per group. The changes in rhizosphere-soil-related variables, microbial community diversity, enzyme activity, and cotton yield were studied. Compared to the control, the available nitrogen content increased by 19.76–62.40%, and soil moisture increased by 2.48–7.72%. The activities of urease, sucrase, and alkaline phosphatase increased, malondialdehyde content decreased, the Soil Plant Analysis Development (SPAD) value increased, and cotton yield increased by 8.94–9.28%. According to the structural equation model, Bacillus subtilis can increase microbial community diversity and network complexity, improve soil nutrients and enzyme activity, and increase cotton yield. This study’s findings may offer a theoretical foundation for enhancing soil quality and raising agricultural yields in arid regions. Full article

Water scarcity and spatial variability in soil fertility are key constraints to stable grain production in the Huang-Huai-Hai Plain. However, the interaction mechanisms between regulated deficit irrigation and soil fertility influencing yield formation and water-nitrogen use efficiency in winter wheat remain unclear. In this study, a two-year field experiment (2022–2024) was conducted to investigate the effects of two irrigation regimes—regulated deficit irrigation during the heading to grain filling stage (D) and full irrigation (W)—under four soil fertility levels: F1 (N: P: K = 201.84: 97.65: 199.05 kg ha⁻¹), F2 (278.52: 135: 275.4 kg ha⁻¹), F3 (348.15: 168.75: 344.25 kg ha⁻¹), and CK (no fertilization). The results show that aboveground dry matter accumulation, total nitrogen content, pre-anthesis dry matter and nitrogen translocation, and post-anthesis accumulation significantly increased with fertility level (p < 0.05). Regulated deficit irrigation promoted the contribution of post-anthesis dry matter to grain yield under the CK and F1 treatments, but suppressed it under the F2 and F3 treatments. However, it consistently enhanced the contribution of post-anthesis nitrogen to grain yield (p < 0.05) across all fertility levels. Higher fertility levels prolonged the grain filling duration by 18.04% but reduced the mean grain filling rate by 15.05%, whereas regulated deficit irrigation shortened the grain filling duration by 3.28% and increased the mean grain filling rate by 12.83% (p < 0.05). Grain yield significantly increased with improved fertility level (p < 0.05), reaching a maximum of 9361.98 kg·ha⁻¹ under the F3 treatment. Regulated deficit irrigation increased yield under the CK and F1 treatments but reduced it under the F2 and F3 treatments. Additionally, water use efficiency exhibited a parabolic response to fertility level and was significantly enhanced by regulated deficit irrigation. Nitrogen partial factor productivity (NPFP) declined with increasing fertility level (p < 0.05); Regulated deficit irrigation improved NPFP under the F1 treatment but reduced it under the F2 and F3 treatments. The highest NPFP (41.63 kg·kg⁻¹) was achieved under the DF1 treatment, which was 54.81% higher than that under the F3 treatment. TOPSIS analysis showed that regulated deficit irrigation combined with the F1 fertility level provided the optimal balance among yield, WUE, and NPFP. Therefore, implementing regulated deficit irrigation during the heading–grain filling stage under moderate fertility (F1) is recommended as the most effective strategy for achieving high yield and efficient resource utilization in winter wheat production in this region. Full article

Salinity has significant impacts on crops, a problem that is exacerbated under climate change conditions. For this reason, research is focused on possible ways to mitigate the impacts by adapting cultivation methods such as administering appropriate materials or formulations to plants. Therefore, this study investigated the effects of calcium (Ca²⁺) supplementation on the growth, physiology, and chemical composition of pomegranate plants (Punica granatum L. cv. ‘Wonderful’) grown under salinity stress. Young self-rooted plants were cultivated in pots containing a sand/perlite (1:1) mixture and irrigated with Hoagland’s nutrient solution amended with NaCl (0, 60, or 120 mM) and CaCl₂·2H₂O (0 or 10 mM). Salinity significantly reduced the fresh and dry weight of aboveground tissues; photosynthetic performance; chlorophyll content; and potassium (K), calcium (Ca), and magnesium (Mg) concentrations, particularly under high NaCl levels. Sodium (Na) accumulation increased in all plant parts, while nitrogen (N), manganese (Mn), and zinc (Zn) concentrations were elevated in basal leaves. Calcium supplementation mitigated several of these adverse effects, especially under moderate salinity. It helped maintain leaf biomass, supported K⁺ retention in roots, partially improved chlorophyll concentration, and limited Na⁺ accumulation in certain tissues. However, Ca²⁺ application did not consistently reverse the negative impacts of severe salinity (120 mM NaCl), and in some cases, interactions between Ca²⁺ and other nutrients such as Mg²⁺ were antagonistic. These findings confirm the inherent salt tolerance of pomegranate and demonstrate that calcium plays a partially protective role under salinity, particularly at moderate stress levels. Further research is needed to optimize Ca²⁺ use in saline agriculture and enhance sustainable cultivation of pomegranate in salt-affected soils. Full article

Groundwater nitrate (NO₃⁻) contamination has emerged as a critical global environmental issue, posing serious human health risks. This study systematically investigated the hydrochemical processes, sources of NO₃⁻ pollution, the impact of land use on NO₃⁻ pollution, and drinking water safety in an urban area of southwestern China. Thirty-one groundwater samples were collected and analyzed for major hydrochemical parameters and dual isotopic composition of NO₃⁻ (δ¹⁵N-NO₃⁻ and δ¹⁸O-NO₃⁻). The groundwater samples were characterized by neutral to slightly alkaline nature, and were dominated by the Ca-HCO₃ type. Hydrochemical analysis revealed that water–rock interactions, including carbonate dissolution, silicate weathering, and cation exchange, were the primary natural processes controlling hydrochemistry. Additionally, anthropogenic influences have significantly altered NO₃⁻ concentration. A total of 19.35% of the samples exceeded the Chinese guideline limit of 20 mg/L for NO₃⁻. Isotopic evidence suggested that primary sources of NO₃⁻ in groundwater include NH₄⁺-based fertilizer, soil organic nitrogen, sewage, and manure. Spatial distribution maps indicated that the spatial distribution of NO₃⁻ concentration correlated strongly with land use types. Elevated NO₃⁻ levels were observed in areas dominated by agriculture and artificial surfaces, while lower concentrations were associated with grass-covered ridge areas. The unabsorbed NH₄⁺ from nitrogen fertilizer entered groundwater along with precipitation and irrigation water infiltration. The direct discharge of domestic sewage and improper disposal of livestock manure contributed substantially to NO₃⁻ pollution. The nitrogen fixation capacity of the grassland ecosystem led to a relatively low NO₃⁻ concentration in the ridge region. Despite elevated NO₃⁻ and F⁻ concentrations, the entropy weighted water quality index (EWQI) indicated that all groundwater samples were suitable for drinking. This study provides valuable insights into NO₃⁻ source identification and hydrochemical processes across varying land-use types. Full article

To identify optimal strategies for high-yield and high-efficiency cultivation under a “short-season direct-seeded cotton with once-only irrigation” regime, we conducted two-year field experiments (2022 and 2023) using a split-plot factorial design with three planting densities (30,000 (D1), 45,000 (D2), and 60,000 (D3) plants·ha⁻¹) and three nitrogen application rates (150 (N1), 180 (N2), and 210 (N3) kg·ha⁻¹). Our study systematically examined how these treatment combinations influenced canopy architecture, physiological traits, yield components, and fiber quality. The results showed that increased planting density significantly enhanced plant height, the leaf area index (LAI), and the number of fruiting branches, with the highest density (D3) contributing to a more compact and efficient canopy. Moderate nitrogen input (N2) significantly increased peroxidase (POD) activity, reduced malondialdehyde (MDA) accumulation, delayed functional leaf senescence, and prolonged the canopy’s photosynthetic performance. A significant interaction between planting density and nitrogen application was observed. The D3N2 treatment (high density with moderate nitrogen) consistently achieved the highest fruiting branch count, boll number per plant, and yields of both seed cotton and lint in both years, while maintaining stable fiber quality. This indicates its strong capacity to balance high yield with quality and maintain physiological resilience. By contrast, the D1N1 treatment (low density and low nitrogen) exhibited a loose canopy, premature photosynthetic decline, and the lowest yield. The D3N3 treatment (high density and high nitrogen) promoted vigorous early growth but reduced stress tolerance during later growth stages, leading to yield instability. These findings demonstrate that moderately increasing planting density while maintaining appropriate nitrogen levels can effectively optimize canopy structure, improve stress resilience, and enhance yield under short-season direct-seeded cotton systems with once-only irrigation. This provides both theoretical underpinning and practical guidance for achieving stable and efficient cotton production under such systems. Full article

Arundo donax L. (giant reed) is a perennial rhizomatous grass with high drought and salinity tolerance, making it a promising low-input bioenergy crop. However, the understanding of the combined effects of irrigation and nitrogen application in salinized soil on physiological adaptations and biomass allocation is still limited. In this study, we conducted a three-factor orthogonal pot experiment with four levels per factor in 2023 and 2024 as follows: salinity (S0: non-saline, S1: low salinity, S2: moderate salinity, S3: high salinity); irrigation amount (W0: 605, W1: 770, W2: 935, W3: 1100 mm); and nitrogen application (N0: 0, N1: 60, N2: 120, N3: 180 kg/ha). This resulted in 14 irrigation-nitrogen-salinity combined treatments. The results showed the following: (1) Irrigation, nitrogen and salinity significantly affected leaf dimensions, photosynthetic rate, plant height, biomass allocation and dry matter of the total plant (p < 0.05). (2) Significant coupling interactions were observed between salinity and irrigation, as well as between nitrogen and irrigation, affecting leaf morphology, plant height, leaf dry matter and total biomass accumulation; a coupling interaction of salinity and nitrogen was found to affect the leaf area, root, stem and leaf dry weight. (3) The S0N2W2 treatment produced the highest dry biomass, which was 2.2 times higher than for the S3N2W2 treatment. (4) Under moderate-salinity conditions (S2), biomass allocation favored stems and leaves, whereas under high-salinity conditions (S3) biomass allocation shifted towards leaves, followed by stems and roots. A combination of 935 mm irrigation amount and 120 kg/ha nitrogen (N2W2) under S1 and S2 is recommended to optimize biomass production. Our study provides practical irrigation and nitrogen management strategies to enhance A. donax cultivation on marginal saline lands, supporting climate-resilient bio-economy initiatives. Full article

Optimizing irrigation and nitrogen (N) management in saline soils is critical for sustainable cotton production in arid regions that have been subjected to climate change. In this study, a two-year factorial field experiment (3 salinity levels × 3 N rates × 3 irrigation quotas) is integrated with the RZWQM2 model to (1) identify water–N–salinity thresholds for cotton yield and (2) to project climate change impacts under SSP2.4-5 and SSP5.8-5 scenarios (2031–2090) in Xinjiang, China, a global cotton production hub. The results demonstrated that a moderate salinity (6 dS/m) combined with a reduced irrigation (3600 m³/hm²) and N input (210 kg/hm²) achieved a near-maximum yield (6918 kg/hm²), saving 20% more water and 33% more fertilizer compared to conventional practices. The model exhibited a robust performance (NRMSE: 5.94–12.88% for soil–crop variables) and revealed that warming shortened the cotton growing season by 1.2–9.5 days per decade. However, elevated CO₂ (832 ppm by 2090) levels under SSP5.8-5 increased yields by 22.6–42.1%, offsetting heat-induced declines through enhanced water use efficiency (WUE↑27.5%) and biomass accumulation. Critically, high-salinity soils (9 dS/m) required 25% additional irrigation (4500 m³/hm²) and a full N input (315 kg/hm²) to maintain yield stability. These findings provide actionable strategies for farmers to optimize irrigation schedules and nitrogen application, balancing water conservation with yield stability in saline-affected arid agroecosystems that have been subjected to climate change. Full article

Nitrogen (N) and organic-source fertilizers in agriculture are important to sustain crop production for feeding the growing global population. However, their use can result in significant greenhouse gas (GHG) emissions, particularly carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O), which are important climate drivers. This review discusses the interactive effects, uncovering both additive and suppressive outcomes of emissions under various soil and climatic conditions. In addition to examining the effects of nitrogen and the nitrogen use efficiency (NUE), it is crucial to comprehend the mechanisms and contributions of organic fertilizers to GHG emissions. This understanding is vital for developing mitigation strategies that effectively reduce emissions while maintaining agricultural productivity. In this review, the current knowledge is utilized for the management of nitrogen practices, such as the optimization of fertilization rates, timing, and methods of application, in terms of the nitrogen use efficiency and the related GHG emissions. Moreover, we discuss the role of organic fertilizers, including straw, manure, and biochar, as a mitigation strategy in relation to GHG emissions through soil carbon sequestration and enhanced nutrient cycling. Important strategies such as crop rotation, tillage, irrigation, organic fertilizers, and legume crops are considered as suitable approaches for minimizing emissions. Even with the progress made in mitigating fertilizer-related emissions, research gaps remain, specifically concerning the long-term effect of organic fertilizers and the interactions between microbial communities in the soil and fertilization practices. Furthermore, the differences in application practices and environmental conditions present considerable obstacles to accurate emission quantification. This review underlines the importance of conducting more thorough research on the combined application of N and organic fertilizers in multiple cropping systems to evolve region-specific mitigation strategies. Full article

The inefficient irrigation strategy is an important factor affecting the yield and water productivity of tomatoes in greenhouses, seriously hindering the development of the cultivation industry. While the impact of irrigation level on tomato growth and yield has been extensively studied, irrigation interval, another crucial component of irrigation schedule, as well as their interaction, remain poorly explored. There were four irrigation levels (W1: 125% ET_c, W2: 100% ET_c, W3: 75% ET_c, and W4: 50% ET_c; ET_c represented crop evapotranspiration) and three irrigation intervals (D1: 4-day interval, D2: 7-day interval, and D3: 10-day interval), aiming to explore the effects of different irrigation intervals and levels on the performance of tomatoes. Here, we showed that the moderate increases in irrigation level and interval promoted root growth, improved nitrogen uptake and distribution, and enhanced plant height, stem diameter, leaf area index, and aboveground biomass, thereby promoting the net photosynthetic rate of plants and fruit yield. The fruit quality indicators of total soluble solids, vitamin C, and soluble sugar decreased with increasing irrigation level but increased with decreasing irrigation interval. Higher irrigation levels increased tomato water consumption and resulted in lower water-nitrogen use efficiency. Overall, compared with W2D2 and W2D3, the yield of W2D1 increased by 8.0% and 26.1%, respectively, and the water productivity increased by 5.7% and 19.3%, respectively, and the soluble sugar increased by 7.1% and 17.5%, respectively. In addition, nitrogen uptake in tomato organs increased and then decreased with the increase of irrigation level, while it consistently increased with decreasing irrigation interval. At the harvest period, the nitrogen uptake in plant organs followed the order of fruit > leaf > stem. Taken together, W2D1 (100% ET_c and 4-day interval) is the recommended irrigation strategy for this experiment, which can provide a theoretical basis and technical support for the sustainable production strategy of greenhouse drip irrigation tomatoes. Full article

In global drought-prone cotton-growing (Gossypium hirsutum L.) areas, saline water irrigation has become a key strategy to alleviate the shortage of freshwater resources. Against this backdrop, the synergistic effect of mineralization degree (MD) and sodium adsorption ratio (SAR) on the rhizosphere microecological regulation mechanism remains unclear. To address this issue, this study constructed an experimental framework of the interaction between MD and SAR, aiming to explore their effects on the bacterial community structure in the rhizosphere of cotton and the soil environment. The soil type in the study area is saline–sodic sandy loam. In the experimental design, three MD levels (3 g/L, 5 g/L, 7 g/L) were set, and under each mineralization condition, three SAR levels (10 (mmol/L)^1/2, 15 (mmol/L)^1/2, 20 (mmol/L)^1/2) were arranged. In addition, local freshwater irrigation was used as the control group (CG), resulting in a total of 10 treatment schemes. The aim of this study was to investigate the effects of varying levels of irrigation water MD and SAR on the structure of bacterial communities in cotton rhizosphere soil and the soil environment. The results indicated that saline water irrigation could enhance the diversity and richness of the bacterial community in the rhizosphere soil of cotton and alter its community structure. Under treatment with the MD of 3 g/L and the SAR of 10 (mmol/L)^1/2, the diversity and richness of the bacterial community in the cotton rhizosphere reached their peak levels. Compared with the CG, the Chao1 index significantly increased by 260 units, while the Shannon index increased by 0.464. When the MD does not exceed 5 g/L, reducing SAR can enhance the diversity and network stability of the rhizosphere bacterial community, thereby synergistically promoting the accumulation of soil nutrients. The key soil environmental factors driving changes in the rhizosphere bacterial community structure mainly include soil moisture content, total nitrogen, nitrate nitrogen, and total organic carbon. The concentrations of total nitrogen, nitrate nitrogen, available phosphorus, and available potassium significantly increased by 19.66%, 26.10%, 89.41%, and 49.76% respectively (p < 0.05). This study provides a theoretical basis for sustainable irrigation and microbial regulation strategies in saline–alkali cotton fields at the theoretical level, and offers a new perspective for revealing the mutual feedback mechanism between bacterial community assembly and soil environment under saline conditions. From a practical perspective, this research offers valuable hands-on experience for optimizing agricultural ecological management in saline–alkali sandy loam soils, thereby contributing to the sustainable development of agriculture on such lands. Full article

Maize production is increasingly challenged by climate change, which affects plant physiology, fungal colonization, and mycotoxin contamination. Aspergillus flavus, a saprophytic fungus, thrives in warm, dry conditions, leading to aflatoxin B1 (AFB1) accumulation, and posing significant food safety risks. Macro- and micro-climatic factors, including temperature, humidity, and precipitation, influence kernel development, leaf wetness duration, and mycotoxin biosynthesis. Nitrogen availability and irrigation play crucial roles in modulating plant responses to these stressors, affecting chlorophyll content, yield parameters, and fungal interactions. To investigate these interactions, a Completely Randomized Design (CRD) was employed from 2020 to 2022 to assess physiological changes in SY Orpheus maize hybrid under varying climatic conditions. Rising temperatures and declining relative humidity (RH) significantly reduced kernel number per ear length from 25.60 ± 0.34 in 2020 to 17.89 ± 0.39 in 2022 (p < 0.05), impacting yield. The AFB1 levels peaked in 2021 (156.88 ± 59.02 µg/kg), coinciding with lower humidity and increased fungal stress. Water availability improved kernel numbers and reduced AFB1 accumulation (p < 0.05) but did not significantly affect the total fungal load (p > 0.05). Nitrogen supplementation enhanced plant vigor, suppressed AFB1 biosynthesis, and influenced spectral indices. Potential confounding factors such as soil variability and microbial interactions may require further investigations. Full article

Water scarcity can negatively affect crop yield, posing a significant threat to global food security, such as drought. Plant growth-promoting rhizobacteria (PGPR), either as single strains or synthetic communities (SynComs), has shown promise in alleviating drought stress in various plant species. In this study, we examined the effects of water limitation on Salvia officinalis and the potential of a SynCom composed of five phosphate-solubilizing, auxin-producing, and/or nitrogen-fixing Gram-negative bacteria to enhance plant growth and drought tolerance. Plant growth, morphology, physiology, and leaf metabolomic profiles were assessed using a combination of physiological measurements and LC-MS untargeted metabolomics. Mild water stress induced a conservative water-use strategy in S. officinalis, characterized by increased root-to-shoot ratio and altered leaf morphology, without compromising photosynthetic performance. SynCom inoculation under well-watered conditions elicited drought-like responses, including transient reductions in stomatal conductance. Leaf metabolomic analysis revealed that inoculation influenced the abundance of several metabolites, including biogenic amines and dipeptides, under both irrigation regimes. Notably, drought stress and SynCom inoculation increased histamine and α-ketoglutaric acid levels, highlighting potential impacts on food quality. Under reduced irrigation, inoculation further modulated leaf morphology and biomass allocation, promoting thicker leaves and increased root biomass allocation. These results demonstrate the ability of the SynCom to modulate plant physiology and metabolism in response to both optimal and reduced irrigation, potentially enhancing drought resilience without directly improving growth. The study also highlights the complex interactions among microbial inoculation, plant stress responses, and leaf metabolite profiles, emphasizing the importance of considering the effects on the production of bioactive compounds when developing microbial inoculants for edible plants. Full article

Intensive and large-scale drip irrigation plays a crucial role in ensuring cotton production in Northwest China. However, significant differences in cotton production have occurred at times within large-scale irrigation systems, and quantitative information on the importance and interactions of factors related to cotton growth and constraints is scarce. In 2018–2019, we monitored six possible constraints (irrigation depth, soil texture, soil salt, soil moisture, soil inorganic nitrogen and soil organic matter) associated with drip irrigation management and seed cotton yields in a collective drip irrigation system (CDIS, composed of several drip irrigation subsystems (DISs)) in southern Xinjiang to assess the importance of different factors and identify the main constraints. In 2023, other more refined field trials were conducted to further evaluate the influencing mechanism of the main constraints on crop growth in one typical DIS within the selected CDIS. The results revealed large yield differences within the CDIS; although the average seed cotton yield was good (2018: 8051 kg ha⁻¹, 2019: 6617 kg ha⁻¹). Excessive irrigation depths (>500 mm) and coarse soil texture (sand content > 70%) were identified as the main constraints, affecting more than 45% of the plant area in the CDIS based on boundary line analysis (a typical analysis method to study the responses between variables) The results from the DISs revealed that the two constraints directly affected the soil moisture and soil inorganic nitrogen in the root zone, which reduced the effectiveness of irrigation and fertilization under drip irrigation. The Structural Equation Model (used to evaluate the causal relationships among multiple variables) revealed that both irrigation depth and soil texture indirectly affect yield by affecting soil inorganic nitrogen and plant N uptake and that soil nitrogen management is critical in resisting yield decline caused by constraints. An optimized irrigation schedule, improved uniformity of the drip irrigation network and adjusted drip fertilization strategies could be used for site-specific management to address the yield decline due to the main constraints and improve water and fertilizer use efficiency under drip irrigation management. Full article